If you're not regularly checking Facebook, you may not realise if one of your friend's has posted content to your Timeline, sent you a message or simply commented on a photo or status you have updated. However, the social network allows you to opt-in to notifications, either by email or text message. Here's how to adjust the notification settings for your Facebook account.
Log into your Facebook account and from the drop down menu next to Home, select Account Settings.
From the menu on the left-hand side, select notifications.
Scroll down to the section marked All notifications and then to the right-hand side of the Facebook icon, press Edit.
The section will be expanded and list a number of different activities, such as someone posting on your wall or sending you a message. To ensure you are notified by email, simply check the box next to it. When finished press Save Changes and email notifications will be enabled. It's worth noting that will this section allows you to receive a notification if someone 'likes' a post to your Timeline, you'll need to expand the section labelled Wall Comments if you want to be emailed any time someone comments on your timeline posts.
If you want to turn mobile notifications (text messages) on, then you need to select Mobile from the menu on the left-hand side, rather than notifications, and then select On or Off and unchecking/checking the boxes you want notifications for.